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101.
目的:研究唐古特大黄提取物不同成分的泻下作用。方法:采用炭末推进方法、酚红排空方法进行肠推进实验,观察大黄提取物各成分(15 g·kg-1)对小鼠小肠推进和肠水分吸收、大鼠大肠运动的影响。结果:唐古特大黄提取物不同成分与对照组相比,对小鼠小肠推进和肠水分吸收、大肠推进作用均有显著性差异(P<0.01);与大黄水煎液、醇提液相比,泻下活性存在一些差异。结论:唐古特大黄提取物不同成分均有显著的泻下作用,但与大黄水煎液和醇提液相比有一些差异。  相似文献   
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103.
OBJECTIVE: The existence of a peripheral neuropathy after exposure to polychlorinated dioxins (PCDD) is still discussed, as studies concerning dioxin effects on the peripheral nervous system are rare and contradictory. MATERIAL AND METHODS: Clinical and neurophysiological examinations (motor conduction velocity of the peroneal nerve, sensory conduction velocities of the sural and ulnar nerves) were made in 156 dioxin exposed workers (42 with, 114 without cloracne) from one pesticide producing plant. Because of known risk factors for peripheral neuropathy, 7 workers with and 28 without cloracne were excluded from further analysis. RESULTS: Workers with chloracne had a significantly higher exposure against PCDD as documented by back calculated lipid levels. They complained significantly more often of sexual impotence (28.6% compared to 5.8% of workers without chloracne, P<0.001), had significantly more frequent clinical signs of a sensory neuropathy (= abnormal sensory findings plus deep tendon reflex abnormalities) restricted to the legs (17.1% compared to 1.2%, P<0.001), had significantly more frequent > or =2 neurophysiologic abnormalities (34.3% compared to 14.0%, P<0.025), and had significantly lower mean amplitudes of the motor compound muscle potential of the peroneal nerve. CONCLUSION: PCDD has a mild toxic effect on the peripheral nervous system manifesting as mild sensory neuropathy of the legs in a minority of the most severely exposed persons.  相似文献   
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105.
Summary In a period of 36 months, 875 patients underwent arthroscopy under local anesthesia as an outpatient procedure; 523 of these underwent arthroscopic surgery. The patients left the hospital within 1 h of completion of surgery. There were only a few complications. This is shown to be a safe and reliable method, which not only decreases morbidity but also lowers hospital and patient costs. The results obtained compare favorably with those published on arthroscopic surgery performed under general anesthesia.  相似文献   
106.
Decellularized human dermis as a potentially ideal scaffold for dermal substitution in severe burns was examined in a two‐staged animal experiment. In an initial step, an in vitro generated composite graft consisting of human keratinocytes and decellularized dermis (AlloDerm®) was transplanted onto nude mice in a short‐term trial (n = 20, 14 days). Subsequently, a combined one‐step grafting of full thickness wounds with both decellularized dermis (in part preincubated with fibroblasts) and cultivated autologous keratinocytes as a cell suspension in fibrin glue was done in a long‐term porcine animal model (n = 10, 6 months). In both series, macroscopic wound healing was evaluated by planimetry. Histological investigations included morphological as well as immunohistochemical parameters. The short‐term study showed both successful integration of the composite grafts and reduction of wound contraction compared with the control group (epithelial grafts). The long‐term porcine study displayed reduced myofibroblast formation and contraction in the wounds that had been treated with fibroblast‐preincubated dermis. After 4 weeks, a decline of the structural integrity of the dermal matrix could be noticed. The utility of decellularized dermis as template for both dermal reconstitution and keratinocyte delivery vehicle was shown. The closure of full thickness wounds by a single‐step combination of an autologous keratinocyte fibrin sealant suspension and acellular dermis in a pig animal model could be shown. Incorporation of fibroblasts led to reduced wound contraction but could not prevent the loss of dermal integrity. The engineered ‘skin’ remained viable and stable over a period of 6 months.  相似文献   
107.
Two groups of patients with aneurysmal subarachnoid haemorrhages--111 patients who underwent surgery within three days of haemorrhage, and 203 patients who underwent operations four or more days after the haemorrhage--were compared. No significant differences were found in outcome between the two groups. This indicates that early operation, which has the advantage of minimizing the risk of recurrent haemorrhage, is safe. The importance of the early diagnosis of subarachnoid haemorrhage and of an urgent referral for neurosurgical management is stressed.  相似文献   
108.
Twenty-six patients (4 months to 6 years old) with achondroplasia complicated by sleep apnea and/or other neurologic manifestations underwent plain computed tomography (CT) of the craniocervical junction; six also underwent CT myelography. For objectification, multiplanar reconstruction was used to complement axial plane measurements by providing coronal and sagittal measurements; multiplanar reconstruction also improved perception of the longitudinal relationships between the brain stem and subarachnoid space. A narrow subarachnoid space was found in all 26 patients; marked cord compression was present in nine, six of whom underwent CT myelography. These six had marked focal obliteration of the subarachnoid space on both plain CT and CT myelography. Since the subarachnoid space immediately above and below the craniocervical junction is normally capacious, when marked constriction was present, no additional information could have been gained from CT myelography. Thus, plain CT was shown to be sufficient for surgical planning (suboccipital decompression) in nine patients with cord compression due to achondroplasia.  相似文献   
109.
110.
Despite considerable progress in the knowledge about pathophysiology of cardiac allograft vascular disease (CAVD), only few systematic studies are available, characterizing the natural course during long-term follow-up after heart transplantation (HTX). Therefore, we analyzed in 354 heart transplant recipients (305 male, 45.9 +/- 11.2 years, mean observation period 5.8 +/- 3.0 years, range 0.9-12.4 years) the results of 1129 coronary angiograms under the aspects of development, severity, localization, and progression of disease related to the prognosis of patients. As expected an increasing prevalence was found over time with a luminal obstruction > or = 30% in 83% of all patients more than 10 years after HTX. Coronary artery stenosis (> or = 50%) at initial diagnosis was predominantly localized in the LAD (46%) followed by RCX (31%) and RCA (23%). Angiographic risk profiles with an impaired prognosis could be identified in the form of an early development (< 4 years post HTX) of disease (p = 0.03), luminal obstruction > 50% (p = 0.001), and multivessel appearance at first diagnosis (p = 0.02) as well as in progressive forms of CAVD (p = 0.001). Summarizing, CAVD is a frequent finding in HTX recipients. Especially in patients with early onset, progressive, and advanced stages of disease it represents a prognostically limiting complication following HTX. Identification of the natural course is of major importance defining the need and efficacy of future palliative therapeutical approaches.  相似文献   
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